College of Water Sciences, Beijing Normal University, Beijing 100875, China.
College of Water Sciences, Beijing Normal University, Beijing 100875, China.
Sci Total Environ. 2019 Nov 1;689:1228-1234. doi: 10.1016/j.scitotenv.2019.06.373. Epub 2019 Jun 24.
Weather and climate extremes, such as droughts and hot extremes, may result in marked damages to crop yields and threaten regional and global food security. Understanding the relationship between climate extremes and crop yields is of critical importance for food security under a changing climate. The objective of this study is to investigate the probabilistic variability of maize yields with respect to compound dry-hot events, which has been shown to be more stressful to crops compared with individual dry or hot events. A multivariate model is first constructed to model the joint behavior of the dry condition, hot condition, and crop yields. The response of crop yields under different dry, hot, and compound dry-hot conditions at national and global scales is then investigated based on the conditional distribution. For the major maize producing countries (top 5), the probability of maize yield reduction could increase by from 0.07 to 0.31 (from 0.04 to 0.31) when the individual extreme drought (extreme hot) conditions changed to compound dry-hot conditions. The probabilistic evaluation of compound dry-hot events' impacts on maize yields is expected to provide useful insights for the mitigation of compound events and their impacts under a changing climate.
极端天气和气候，如干旱和热浪，可能会对作物产量造成显著的破坏，并威胁到区域和全球的粮食安全。了解气候极端事件与作物产量之间的关系对于应对气候变化下的粮食安全至关重要。本研究旨在研究玉米产量与复合干热事件的概率可变性，与单一的干旱或炎热事件相比，复合干热事件对作物的压力更大。首先构建一个多元模型来模拟干燥条件、炎热条件和作物产量的联合行为。然后根据条件分布研究不同干燥、炎热和复合干燥-炎热条件下的全国和全球范围内的作物产量的响应。对于主要的玉米生产国（前 5 名），当单个极端干旱（极端炎热）条件转变为复合干燥-炎热条件时，玉米产量减少的概率可能会增加 0.07 到 0.31（从 0.04 到 0.31）。对复合干热事件对玉米产量影响的概率评估有望为缓解气候变化下的复合事件及其影响提供有用的见解。
